Nematicidal activity of Paecilomyces lilacinus 6029 cultured on Karanja cake medium
Nematicidal activity of Paecilomyces lilacinus 6029 cultured on Karanja cake medium
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DOI：
10.1016/j.micpath.2014.08.007
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发表时间：
2014-10-01
影响因子：
3.8
通讯作者：
Dalela, Manu
中科院分区：
文献类型：
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作者：
Sharma, Abhishek;Sharma, Satyawati;Dalela, Manu
拮抗真菌通过分泌胞外水解酶和次生代谢产物寄生于根结线虫。本研究体外生物测定结果表明，从Karanja饼培养基中提取的淡紫色拟青霉6029培养滤液，在12 h内，可杀灭100%的黑线蛾幼虫，而用Czapeck-Dox滤液对黑线蛾幼虫的死亡率仅为78.28%。无论培养基如何，当孵育15天时，发现滤液对线虫的毒性更大。傅里叶变换红外光谱预测了滤液中酚类和醇类化合物的存在。此外，对真菌滤液中的活性代谢物进行了部分表征。pH稳定性试验表明，滤液在所有pH范围内均具有线虫毒性，pH值较低的滤液对线虫的毒性更大。有趣的是，相同pH值的缓冲液没有任何杀线虫作用。煮熟滤液（死亡率为98.2%）与未煮熟滤液（死亡率为100%）的杀线虫活性无显著差异。乙酸乙酯和冻干水提取物的杀线虫活性高于己烷提取物，这表明紫丁香6029产生的活性化合物具有极性性质。(C) 2014 Elsevier Ltd.版权所有。
Antagonistic fungi parasitize root-knot nematodes through secretion of extracellular hydrolytic enzymes and secondary metabolites. In present study, in vitro bioassay showed that Paecilomyces lilacinus 6029 culture filtrate from Karanja cake medium killed 100% Meloidogyne incognita larvae while only 78.28% mortality was recorded by Czapeck-Dox filtrate within 12 h of exposure. The filtrate, irrespective of culture medium, was found to be more nematotoxic when incubated for 15 days. Fourier Transform infrared spectroscopy predicted the presence of phenolic and alcoholic compounds in the filtrate. Furthermore, the active metabolites in fungal filtrate were partially characterized. pH stability test revealed that nematotoxicity of the filtrate appeared at all range of pH with low pH filtrate possessing more toxicity against M. incognita. Interestingly, buffers of same pH value did not show any nematicidal effect. No significant difference in nematicidal activity was observed between boiled (98.2% mortality) and unboiled culture filtrate (100% mortality). Ethyl acetate and lyophilized aqueous extracts produced higher nematicidal activity than a hexane extract indicating polar nature of active compounds produced by P. lilacinus 6029. (C) 2014 Elsevier Ltd. All rights reserved.